Remove some single-SHB assumptions.

Make wtap_file_get_shb() take a section number argument, and update code
that called it.  In most cases, we convert the code to iterate over
sections; in cases where a big code change would be required, we
temporarily pass it 0 and mark the code as "needs to be updated for
multiple sections".

Eliminate cf_read_section_comment(); in calls outside file.c, other code
directly calls the libwiretap routines it calls and, inside file.c, we
just transplant the code and then fix it not to assume a single SHB.

Change-Id: I85e94d0a4fc878e9d937088759be04cb004e019b
Reviewed-on: https://code.wireshark.org/review/37000
Petri-Dish: Guy Harris <gharris@sonic.net>
Tested-by: Petri Dish Buildbot
Reviewed-by: Guy Harris <gharris@sonic.net>

2 files changed, 24 insertions, 8 deletions

diff --git a/wiretap/wtap.c b/wiretap/wtap.c
index f244f61d5c..3fae62170d 100644
--- a/wiretap/wtap.c
+++ b/wiretap/wtap.c
@@ -95,13 +95,19 @@ wtap_file_tsprec(wtap *wth)
 	return wth->file_tsprec;
 }
 
+guint
+wtap_file_get_num_shbs(wtap *wth)
+{
+	return wth->shb_hdrs->len;
+}
+
 wtap_block_t
-wtap_file_get_shb(wtap *wth)
+wtap_file_get_shb(wtap *wth, guint shb_num)
 {
-	if ((wth == NULL) || (wth->shb_hdrs == NULL) || (wth->shb_hdrs->len == 0))
+	if ((wth == NULL) || (wth->shb_hdrs == NULL) || (shb_num >= wth->shb_hdrs->len))
 		return NULL;
 
-	return g_array_index(wth->shb_hdrs, wtap_block_t, 0);
+	return g_array_index(wth->shb_hdrs, wtap_block_t, shb_num);
 }
 
 GArray*
diff --git a/wiretap/wtap.h b/wiretap/wtap.h
index ee47294879..b73263820b 100644
--- a/wiretap/wtap.h
+++ b/wiretap/wtap.h
@@ -1861,19 +1861,29 @@ WS_DLL_PUBLIC
 int wtap_file_tsprec(wtap *wth);
 
 /**
+ * @brief Gets number of section header blocks.
+ * @details Returns the number of existing SHBs.
+ *
+ * @param wth The wiretap session.
+ * @return The number of existing section headers.
+ */
+WS_DLL_PUBLIC
+guint wtap_file_get_num_shbs(wtap *wth);
+
+/**
  * @brief Gets existing section header block, not for new file.
- * @details Returns the pointer to the existing SHB, without creating a
+ * @details Returns the pointer to an existing SHB, without creating a
  *          new one. This should only be used for accessing info, not
  *          for creating a new file based on existing SHB info. Use
  *          wtap_file_get_shb_for_new_file() for that.
  *
  * @param wth The wiretap session.
- * @return The existing section header, which must NOT be g_free'd.
- *
- * XXX - need to be updated to handle multiple SHBs.
+ * @param shb_num The ordinal number (0-based) of the section header
+ * in the file
+ * @return The specified existing section header, which must NOT be g_free'd.
  */
 WS_DLL_PUBLIC
-wtap_block_t wtap_file_get_shb(wtap *wth);
+wtap_block_t wtap_file_get_shb(wtap *wth, guint shb_num);
 
 /**
  * @brief Gets new section header block for new file, based on existing info.